This invention relates generally to improvements in the formation and installation of dental implants, and more particularly to dental implants having a metallic bone-embedded fixture with which a post is interfaced to support a prosthesis superstructure.
Surgical techniques for implantation of dental prostheses by means of a metallic bone-embedded fixture are well known as disclosed for example in U.S. Pat. Nos. 4,824,372, 4,872,839 and 4,934,935 to Jorneus et al., Brajnovic and Edwards, respectively. According to the Jorneus et al. and Brajnovic patents, a titanium bone-embedded fixture is interfaced with a metallic abutment post, on which the superstructure is supported, the post having an internally shouldered access bore through which a screw fastener is inserted to axially hold the implant components assembled. Various problems and restrictions arise, however, in the attachment and retention of superstructures to such abutment posts.
U.S. Pat. No. 4,850,870 to Lazzara et al. is directed to specific examples of attachment and retention of superstructure on metallic abutment posts interfaced with bone-embedded implant fixtures to which the posts are secured by screw fasteners. The superstructure according to the Lazzara et al. patent includes a separate coping portion secured by means of another screw fastener to the core portion of the abutment post.
U.S. Pat. No. 4,304,553 to Heinke et al. is also of interest because it discloses a superstructure support post made of aluminum oxide. However, such post is formed integral with the bone-embedded fixture so as to introduce various problems affecting installational flexibility and implant adjustment or repair.
It is therefore an important object of the present invention to provide an improved dental implant assembly and an associated installational procedure to facilitate customized formation and fitting of dental prostheses with greater economy and flexibility.
A further object of the invention in accordance with the foregoing object is to provide a dental implant assembly that is less likely to be irreparably damaged and more readily repaired.
Yet another object of the invention is to provide a dental implant assembly having other desireable attributes not heretofore available, such as increased strength and more effective fluid sealing of the gum tissue region in which a separate abutment post is interfaced with the bone-embedded fixture to which it is attached by means of a screw fastener.